Automatic motor-driven pencil sharpener



Nov. 3, 1953 w. E. ANGELL AUTOMATIC MOTOR-DRIVEN PENCIL SHARPENER 2 Sheets-Sheet 1 Filed Dec. 24, 1951 INVENTOR. aafiu Walter Eugene Angel! BY QM Patented Nov. 3, 1953 PATENT OFF iCE.

AUTOMATIC MOTOR-DRIVEN PENCIL SHARPENER Walter Eugene Angeli, Brooklyn, .N. Y.

Application December '24, 1951, Serial'No. 263,029

.2 Claims. (C1. 12.0--96) This invention relates generally to a pencil sharpener, and more particularly to a pencil sharpener which is powered by an automaticmotor drive means.

The primary object of this invention is to provide an improved electric pencil sharpener in which cutting blades are automatically rotated by an electric motor upon application of a pencil between the cutting blades.

Another object of this invention is to provide an improved automatic motor driven pencil sharpener having a guide for aligning pencils with the cutting blade, and switch means for the electric motor associated with the guide.

Another object of this invention is to provide an improved automatic motor driven pencil sharpener having switch means which automatically start the electric motor when a pencil is inserted between the cutting blades, and automatically shuts off the electric motor when the pencil is removed from between the cutting blades.

Another object of this invention is to provide an improved automatic motor driven pencil sharpener having a compartment for receiving the shavings cut from pencils in the process of sharpening them, and when the means in said compartment for determining the amount of shavings within the compartment.

Another object of this invention is to provide a shaving compartment for a pencil sharpener, said shaving compartment having a door for emptying same, and latch means for retaining the door in closed position.

A further object of this invention is to provide an improved housing for an automatic motor driven pencil sharpener having a compartment for receiving the motor and a separate compartment for receiving the cutting blades and shavings cut from pencils in the process of sharpening them.

With these objects definitely in view, this invention resides in certain'novel features of construction, combination and arrangement of ele' ments and portions as will be hereinafter described in detail in the specification, particularly pointed out in the appended claims, and illustrated in the accompanying drawings which are a material part of this application, and in which: Figure 1 is a perspective view of the improved automatic motor driven pencil sharpener; which is the subject of this invention, a pencil being shown disposed within the pencil receiving guide, the pencil being illustrated by dotted lines;

Figure 2 is an enlarged central transverse vertical sectional view through the automatic motor driven pencil sharpener of Figure 1 and taken substantially upon the plane indicated by the section line 22 of Figure 3, and showing the internal construction of the motor and the cutting blades;

Figure 3 is a transverse horizontal sectional View taken substantially upon the plane indicated by the section line 33 of Figure 2 and showing the manner in which the cutting blades are mounted in the housing, and the specific construction of the door latching means; I

Figure 4 is a fragmentary horizontal sectional View taken substantially upon the plane indicated by the section line 4-4 of Figure 2 and showing the connection between the electric motor and the cutting blades of the pencil sharpening port'ion;

Figure 5 is a fragmentary transverse horizontal sectional view taken substantially upon the plane indicated by the section line 5-5 of Figure 2 and showing the construction of a guard for preventing shavings from coming into engagement with the motor shaft;

Figure 6 is a fragmentary transverse vertical sectional view taken substantially upon the plane indicatedby the section line E55 of Figure 3 and showing the construction of the latch means for the door through which the shavings are re moved, and showing the specific relation of the electrical contacts associated therewith;

Figure '7 is a transverse horizontal sectional view taken substantially upon the plane indicated by the section line '!1 of Figure 2 and showing the manner in which the electric motor is disposed within the housing, and the arrangement of the Wiring thereto;

Figure 8 is a fragmentary top plan view of the housing and showing the construction of the guide means for a pencil and its associated switch for automatically operating the electric motor; and,

Figure 9 is a schematic diagram of the elec trical circuit for the motor of the pencil sharp= ener.

tom wall I4 adjacent the corners thereof are a plurality of semi-spherical rubber supporting elements 24.

Referring now to Figures 2 and 7, it will be seen that the top and bottom walls I2 and I 4, respectively, are secured to the end and side walls by a plurality of conventional fasteners 26 which are threadedly secured to connecting blocks 28 mounted in the corners formed by intersecting side and end walls. The housing I is provided with a transverse partition wall 30 which divides the housing into a motor compartment 32 and a cutting blade and shaving receiving compartment 34.

Mounted within the motor compartment 32 is an electric motor 30 having an armature shaft 38 and a mounting base 40. The mounting base 40 of the electric motor is secured to an upstanding flange 42 of an L-shaped bracket by a plural ity of bolts 44. A horizontal flange 46 of the mo tor mounting bracket is secured to the bottom wall I4 of the housing by a plurality of screws 48.

Referring now to Figure 2 in particular, it will be seen that the lower end of the armature shaft 38 is provided with a fan 50 for cooling the elec tric motor 36. The fan 50 is in alignment with an enlarged opening 52 in the bottom wall I4. The upper end of the armature shaft 38 is journaled in a flange bushing 54 carried by the partition wall 30 in alignment with the electric motor 36.

Mounted within the cutting blade compartments 34 and secured to the inner side of the end wall 22 by screws 56 is a conventional pencil sharpener mounting support 58. Referring to Figure 2 in particular, it will be seen that the mounting support 53 is disposed horizontally instead of in its usual vertical position. Rotatably carried by the mounting support 53 are a pair of cutting blades 60 which are rotatably journaled between the mounting support 58 and a bracket 62 carried by the support 58. Extending downwardly from the support 53 is a tubular bushing 64 in which is rotatably mounted a driveshaft 66. The cutting blades 60 are connected to the driveshaft 6% by conventional gear means (not shown). Rigidly secured to the end of driveshaft 66 is a portion of a crank handle 68 for driving the driveshaft 06. It will be understood that the mounting support 58, the blade 60, the driveshaft 66, and the other associated elements are parts of a conventional pencil sharpener.

Referring now to Figures 2 and 4 in particular, it will be seen that carried by the upper end of the armature shaft 36 is a plate I0 having a boss I2 on its underside. The boss '12 has a centrally disposed bore I4 in which is received the upper end of the armature shaft 38. The armature shaft 38 is maintained within the bore 14 by a locking screw I6 carried by the boss I2. Carried by the plate It is a plurality of upstanding arms in the form of threaded bolts I8 which are secured to the plate 70 by nuts 80. The short portion of the handle 60 is disposed between adjacent bolts IS so that when the bolts I8 are rotated by the motor 36, the handle 08 is also rotated in order that the driveshaft 63 may drive the cutting blades 60.

Referring now to Figures 2 and 8, it will be seen that the top wall I2 is provided with a central aperture 82 in which is mounted a guide member 84. The guide member 84 is provided at its lower end with a flange portion 86 bearing against the underside of the top wall I2. Adjacent the upper surface of the top Wall I2, are the guides 84 divided with an opening 88 in one side thereof and an outwardly flared wall portion 90. It will be noted that the guide 84 is in alignment with an aperture 92 through the bracket 62 of the pencil sharpener for receiving a pencil. Extending through the opening 88 in the guide 84 and in sliding relation thereto is a sliding contact 94. The sliding contact 34 is slidably mounted in a guide 96 secured to the top wall I2 by a bolt 98. The guide 96 is provided with a U-shaped bracket I00 which overlies the sliding contact 94 and is provided with a tension spring I02 connected to an upstanding tab I04 on the sliding contact 94 and urging the contact toward the guide 84. The sliding contact 94 is provided with an upwardly and rearwardly directed flange I06 for engaging the outwardly flared side wall portion of the guide which also acts as a stop member and limits the inward motion of the sliding contact 64 through the opening 68 in the guide 84.

Also carried by the top wall I2 is a V-shaped contact I08 which is rigidly secured to the top wall by a bolt H0 in fixed relation thereto and having a flange overlying the guide 06 and the sliding contact 94. Referring to Figure 2, we readily see that when a pencil is moved downwardly through the guide 84 towards the pencil sharpener, that the pencil will engage the flange I06 and move the sliding contact 94 to the right and out of the opening 88 in the guide 8d. When the sliding contact 94 moves to the right, the tab I04 engages the overlying flange of the fixed contact I08 and completes a circuit to the electric motor 36. The wiring detail of the electric motor will be described in more detail hereinafter.

In order that it may be determined when the compartment 34 is filled with shavings, the front wall I6 is provided with a window opening II 2 which is closed by a sheet of transparent plastic I; 4 secured to the inner side of the front wall In order that the shavings disposed in the compartment 34 will not clog the bushing 54 on which the armature shaft 30 rotates, there is secured to the upper side of the partition wall 30 a U shaped guard II6 which partially surrounds the upper end of the bushing 54 and the armature shaft 38.

In order that the compartment 34 may be emptied of shavings periodically, the end wall 20 is provided with an opening I it which is closed by a hinged door I20. The door I20 is carried by a conventional hinge I22 which is secured to both the door I20 and the rear wall I8 by conventional fasteners I24.

Referring now to Figure 3 in particular, it will be seen that the door I20 is provided with a keeper member having a flange I26 secured to the inner side of the door by a screw I28. Extending normal to the flange I26 is a second flange i30 terminating in a lip portion I32. Secured to the front wall I6 is a spring latch I34 having a lip portion I36 in engagement with the lip I32, and an ofiset flange portion I38 secured to the inner side of the front wall I6 by the screw I40. Also carried by the front wall I6 in alignment with the spring latching member I34 is a headed rod member I42 by which the latching member I34 may be released from the keeper carried by the door I20. Secured to the rear wall It by a screw I44 is a leaf spring I46 which engages the inner side of the door I20, and urges the door to an open position.

The housing I is provided with a pair of leadin wires I48 and I50 which are adapted to being connected to any convenient electrical source. Referring to Figure 6 in particular, it will be seen that the lead-in wire I48 passes through the housing I0 and is secured to a. screw I52 which also secures a fixed contact I54 to the front wall IS in a position underlying the spring latching member I34. The fixed contact I54 is normally in contact with the spring latching member I34 when the door I is in its closed latched position. Secured to the spring latching member I38 by the screw I40 is a wire I58 which is secured to one of the terminals of the motor 36.

The other lead-in wire I50 extends upwardly through the partition wall I and is secured to the fixed contact I08 by the bolt H0 carried by the top wall I2 of the housing. A wire I58 is secured to the bolt 98 which secured the guide 96 to the top wall I2 and extends through the partition wall 30, and is connected to the other terminal of the motor 36.

As will be readily seen by referring to the wiring diagram of Figure 9, the switch formed by the latch members of the door I20 are normally closed, and the switch associated with the guide means 84 carried by the top wall I2 is normally open. When a pencil is disposed within the guide 84, the sliding contact 94 engages the fixed contact I08 and closes the circuit thereby supplying current to the electric motor 39 which in turn revolves the cutting blades 60 to sharpen the pencil disposed within the guide 84 and between the blades. However, when the rod I42 is pushed inwardly to disengage the latching member I34 from the keeper carried by the door I20 in order to open the door I 20, the switch portion of the latch is opened and the circuit to the motor 36 is broken. By the use of the switch attached to the latch means for the door I20 injury to the hand is prevented as the cutting blades 60 will not be operated by the motor 36 even if a pencil is disposed within the guide 84 as long as the rod I42 is remained pressed down to break the contact between the spring latching member I34 and the fixed contact I54.

It will be noted that the housing I0 is formed of a plastic material or some other similar material having insulating properties due to the fact that the screws which are part of the electrical circuit are secured directly to the sides and top walls of the housing.

The operation of this machine will be under stood from the foregoing description of the mechanical details thereof, taken in connection with the above recited objects and the drawings. Further description would appear to be unnecessary.

Minor modification of the machine, varying in minor detail from the embodiment of the machine illustrated and described here, may be resorted to without departure from the spirit and scope of this invention, as defined in the appended claims.

Having described the invention, what is claimed as new is:

1. For use in an electric pencil sharpener of the type having a motor driven cutter and a pencil guide carried by a wall of an enclosing housing in alignment with the cutter; a control switch adapted to control operation of the motor, said control switch being mounted on said wall and operatively associated with said pencil guide, said control switch comprising a fixed contact carried by said wall, a movable contact slidably mounted on said wall, said movable contact having an end portion slidably disposed in an opening in said pencil guide for engagement by a pencil, said guide being outwardly flared to form a stop, said end portion including an upwardly and rearwardly disposed flange normally engaging said stop, a spring member connected to a second flange at an opposite end of said movable contact for urging the same towards said pencil guide.

2. The switch of claim 1 wherein said second flange is positioned in alignment with and adjacent said fixed contact for engagement therewith upon movement of said movable contact by a pencil inserted in said pencil guide.

WALTER EUGENE ANGELL.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,395,627 Binkley Nov. 1, 1921 1,788,038 Gawron Nov. 25, 1930 2,184,176 Blake Dec. 19, 1939 2,199,471 Vacca May 7, 1940 2,214,890 Rhodes Sept. 17, 1940 2,266,269 Romeiser Dec. 16, 1941 2,408,767 Fleming Oct. 8, 1946 

